Communication devices, particularly portable communication devices such as handheld two-way radios, are being increasingly used in the transmission of digital data such as image data, audio data, video data, and other digital information. To submit digital images, or other digital media for evidentiary purpose, some form of validation must be provided to indicate that the digital data is authentic and has not been tampered with. Such authentication may be achieved, for example, by adding a watermark to the digital data, creating a digital fingerprint, or encrypting the digital data.
It may also be beneficial to move the digital data to a secure holding area soon after the digital data is created to reduce any risk of the data being tampered with. The process of moving data to a secure holding area often involves moving a large amount of data associated with the image, supporting metadata and the digital fingerprint or watermark across a communications link where it can be securely stored. Transferring large amounts of data is typically not a problem with high bandwidth communication systems, however in narrowband systems, for example, Terrestrial Trunked Radio (TETRA) communication systems, the data bandwidth is limited thereby forcing users to utilize a less secure public network such as a 3G network to transfer digital data. Alternatively, the digital data can remain stored on the communication device, but the increased risk of image tampering makes this an unattractive option.
Accordingly, there is a need for communication devices, such as handheld two-way radios, to be able to authenticate and transfer secure digital data over narrowband networks.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present disclosure.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.